The principal goal of the research for the coming year will be to investigate parathion-drug interactions in mice, rats and monkeys. I particularly want to compare the therapeutic effectiveness of anticholinergic drugs which act centrally and peripherally, such as atropine and scopolamine, with the effectiveness of anticholinergic drugs which act peripherally only, such as methyl atropine, methyl scopolamine and 2-PAM. In mice and rats the endpoints used to study these interactions will be the durations of phases of the maximal electroshock seizure, which also were used previously in my studies of the effects of DDT and dieldrin and of DDT-drug interactions. In rats and monkeys, parathion-drug interactions on brain electrical activity will also be studied.